Contribution of intensive silvopastoral systems to animal performance and to adaptation and mitigation of climate change

According to FAO, world demand for animal products will double in the first half of this century as a result of increasing population and economic growth. During the same period, major changes are expected in world climate. Food security remains one of the highest priority issues in developing Latin American countries, a region where livestock production plays a fundamental role. Agricultural activities seriously threaten natural resources; therefore, it is necessary to ensure that livestock production contributes to satisfy the demand for animal products in a sustainable manner. Intensive silvopastoral systems (ISS) are becoming the technology of choice for Colombian and regional livestock sectors because it can help reduce the seasonality of plants and animal production, and therefore contribute to mitigate and adapt to the effects of climate change. We have recently gained knowledge on the nutritional and productive attributes of these systems. However, in recent years, the low carbon approach acquired importance in animal agriculture, which seeks to primarily promote the adoption of programs running parallel activities aimed at adapting to and mitigating climate change. This review outlines projections on the effects of climate change on the livestock industry, presents concepts on Greenhouse Gas flow and highlights evidence in support of the conclusion that ISS is an interesting option to allow the livestock sector in the region to adapt to climate change and to mitigate some of its effects. The adoption of ISS may help to remove up to 26.6 tons of CO2 eq/Ha/yr from the atmosphere.Segundo a FAO, a demanda mundial de produtos de origem animal se duplicará durante a primeira metade deste século como resultado do aumento da população e dos recursos económicos; durante o mesmo período se esperam grandes mudanças no clima em todo o mundo. A segurança alimentar continua a ser uma das questões de maior prioridade no desenvolvimento dos países latino-americanos e a produção pecuária tem um papel fundamental em muitos destes. Todos estes elementos têm estreita relação com a enorme pressão sobre os recursos naturais, portanto, é necessário que a produção pecuária seja feita de uma maneira sustentável. Os sistemas silvipastoris intensivos (SSPi) estão se transformando em uma opção tecnológica de implementação progressiva na pecuária colombiana e da região porque podem reduzir a estacionalidade da produção vegetal e animal, portanto, podem mitigar os efeitos das mudanças climáticas e adaptar-se a eles. Nos últimos anos ocorreram avanços no conhecimento sobre os aspectos nutricionais e produtivos destes sistemas. No entanto, recentemente começou a ter importância o enfoque da agricultura com baixa produção de carbono que visa, principalmente, delinear programas de desenvolvimento onde se executem paralelamente atividades destinadas à adaptação e mitigação das mudanças climáticas. Esta revisão apresenta algumas projeções sobre os efeitos das mudanças climáticas na pecuária, apresenta alguns conceitos sobre o fluxo de gases do efeito estufa (GEEs) em sistemas de produção animal. Destaca algumas evidências para apoiar que os SSPi são uma opção interessante para permitir que a pecuária na região se adapte às mudanças climáticas e mitigue alguns dos seus efeitos, pois a adoção dos SSPi pode ajudar a remover até 26,6 tôn. CO2 eq/Ha/ano a partir da atmosfera.Según la FAO, la demanda mundial de productos de origen animal se duplicará durante la primera mitad de este siglo como resultado del incremento de la población y del crecimiento económico y durante el mismo período se esperan grandes cambios en el clima a nivel mundial. La seguridad alimentaria sigue siendo una de las cuestiones de más alta prioridad en el desarrollo de los países latinoamericanos y la producción ganadera tiene un papel fundamental en muchos de estos países. Todos estos elementos tienen estrecha relación con la enorme presión sobre los recursos naturales, por tanto, es necesario que la producción ganadera se realice de manera sustentable. Los sistemas silvopastoriles intensivos (SSPi) se están convirtiendo en una opción tecnológica de implementación progresiva en la ganadería colombiana y de la región porque pueden reducir la estacionalidad de la producción vegetal y animal; y por lo tanto pueden mitigar los efectos del cambio climático y adaptarse a ellos. En los últimos años se ha avanzado en el conocimiento sobre los atributos nutricionales y productivos de éstos sistemas. Sin embargo, ultimamamente empieza a tener importancia el enfoque de agricultura baja en carbono que busca principalmente, adelantar programas de desarrollo donde se ejecuten paralelamente actividades orientadas a la adaptación y a la mitigación del cambio climático. La presente revisión incluye algunas proyecciones sobre los efectos del cambio climático en la ganadería, presenta algunos conceptos sobre el flujo de los gases de efecto invernadero (GEI) en los sistemas ganaderos. Resalta algunas evidencias que permiten afirmar que los SSPi son una opción interesante para que la ganadería de la región se adapte al cambio climático y mitigue algunos de sus efectos, dado que con el establecimiento de SSPi se pueden remover hasta 26,6 ton de CO2 equivalentes/Ha/año

Contribution of intensive silvopastoral systems to animal performance and to adaptation and mitigation of climate change

According to FAO, world demand for animal products will double in the first half of this century as a result of increasing population and economic growth. During the same period, major changes are expected in world climate. Food security remains one of the highest priority issues in developing Latin American countries, a region where livestock production plays a fundamental role. Agricultural activities seriously threaten natural resources; therefore, it is necessary to ensure that livestock production contributes to satisfy the demand for animal products in a sustainable manner. Intensive silvopastoral systems (ISS) are becoming the technology of choice for Colombian and regional livestock sectors because it can help reduce the seasonality of plants and animal production, and therefore contribute to mitigate and adapt to the effects of climate change. We have recently gained knowledge on the nutritional and productive attributes of these systems. However, in recent years, the low carbon approach acquired importance in animal agriculture, which seeks to primarily promote the adoption of programs running parallel activities aimed at adapting to and mitigating climate change. This review outlines projections on the effects of climate change on the livestock industry, presents concepts on Greenhouse Gas flow and highlights evidence in support of the conclusion that ISS is an interesting option to allow the livestock sector in the region to adapt to climate change and to mitigate some of its effects. The adoption of ISS may help to remove up to 26.6 tons of CO2 eq/Ha/yr from the atmosphere

Management of coronary disease in patients with advanced kidney disease

BACKGROUND Clinical trials that have assessed the effect of revascularization in patients with stable coronary disease have routinely excluded those with advanced chronic kidney disease. METHODS We randomly assigned 777 patients with advanced kidney disease and moderate or severe ischemia on stress testing to be treated with an initial invasive strategy consisting of coronary angiography and revascularization (if appropriate) added to medical therapy or an initial conservative strategy consisting of medical therapy alone and angiography reserved for those in whom medical therapy had failed. The primary outcome was a composite of death or nonfatal myocardial infarction. A key secondary outcome was a composite of death, nonfatal myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. RESULTS At a median follow-up of 2.2 years, a primary outcome event had occurred in 123 patients in the invasive-strategy group and in 129 patients in the conservative-strategy group (estimated 3-year event rate, 36.4% vs. 36.7%; adjusted hazard ratio, 1.01; 95% confidence interval [CI], 0.79 to 1.29; P=0.95). Results for the key secondary outcome were similar (38.5% vs. 39.7%; hazard ratio, 1.01; 95% CI, 0.79 to 1.29). The invasive strategy was associated with a higher incidence of stroke than the conservative strategy (hazard ratio, 3.76; 95% CI, 1.52 to 9.32; P=0.004) and with a higher incidence of death or initiation of dialysis (hazard ratio, 1.48; 95% CI, 1.04 to 2.11; P=0.03). CONCLUSIONS Among patients with stable coronary disease, advanced chronic kidney disease, and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of death or nonfatal myocardial infarction

Health status after invasive or conservative care in coronary and advanced kidney disease

BACKGROUND In the ISCHEMIA-CKD trial, the primary analysis showed no significant difference in the risk of death or myocardial infarction with initial angiography and revascularization plus guideline-based medical therapy (invasive strategy) as compared with guideline-based medical therapy alone (conservative strategy) in participants with stable ischemic heart disease, moderate or severe ischemia, and advanced chronic kidney disease (an estimated glomerular filtration rate of <30 ml per minute per 1.73 m2 or receipt of dialysis). A secondary objective of the trial was to assess angina-related health status. METHODS We assessed health status with the Seattle Angina Questionnaire (SAQ) before randomization and at 1.5, 3, and 6 months and every 6 months thereafter. The primary outcome of this analysis was the SAQ Summary score (ranging from 0 to 100, with higher scores indicating less frequent angina and better function and quality of life). Mixed-effects cumulative probability models within a Bayesian framework were used to estimate the treatment effect with the invasive strategy. RESULTS Health status was assessed in 705 of 777 participants. Nearly half the participants (49%) had had no angina during the month before randomization. At 3 months, the estimated mean difference between the invasive-strategy group and the conservative-strategy group in the SAQ Summary score was 2.1 points (95% credible interval, 120.4 to 4.6), a result that favored the invasive strategy. The mean difference in score at 3 months was largest among participants with daily or weekly angina at baseline (10.1 points; 95% credible interval, 0.0 to 19.9), smaller among those with monthly angina at baseline (2.2 points; 95% credible interval, 122.0 to 6.2), and nearly absent among those without angina at baseline (0.6 points; 95% credible interval, 121.9 to 3.3). By 6 months, the between-group difference in the overall trial population was attenuated (0.5 points; 95% credible interval, 122.2 to 3.4). CONCLUSIONS Participants with stable ischemic heart disease, moderate or severe ischemia, and advanced chronic kidney disease did not have substantial or sustained benefits with regard to angina-related health status with an initially invasive strategy as compared with a conservative strategy

Health-status outcomes with invasive or conservative care in coronary disease

BACKGROUND In the ISCHEMIA trial, an invasive strategy with angiographic assessment and revascularization did not reduce clinical events among patients with stable ischemic heart disease and moderate or severe ischemia. A secondary objective of the trial was to assess angina-related health status among these patients. METHODS We assessed angina-related symptoms, function, and quality of life with the Seattle Angina Questionnaire (SAQ) at randomization, at months 1.5, 3, and 6, and every 6 months thereafter in participants who had been randomly assigned to an invasive treatment strategy (2295 participants) or a conservative strategy (2322). Mixed-effects cumulative probability models within a Bayesian framework were used to estimate differences between the treatment groups. The primary outcome of this health-status analysis was the SAQ summary score (scores range from 0 to 100, with higher scores indicating better health status). All analyses were performed in the overall population and according to baseline angina frequency. RESULTS At baseline, 35% of patients reported having no angina in the previous month. SAQ summary scores increased in both treatment groups, with increases at 3, 12, and 36 months that were 4.1 points (95% credible interval, 3.2 to 5.0), 4.2 points (95% credible interval, 3.3 to 5.1), and 2.9 points (95% credible interval, 2.2 to 3.7) higher with the invasive strategy than with the conservative strategy. Differences were larger among participants who had more frequent angina at baseline (8.5 vs. 0.1 points at 3 months and 5.3 vs. 1.2 points at 36 months among participants with daily or weekly angina as compared with no angina). CONCLUSIONS In the overall trial population with moderate or severe ischemia, which included 35% of participants without angina at baseline, patients randomly assigned to the invasive strategy had greater improvement in angina-related health status than those assigned to the conservative strategy. The modest mean differences favoring the invasive strategy in the overall group reflected minimal differences among asymptomatic patients and larger differences among patients who had had angina at baseline

Initial invasive or conservative strategy for stable coronary disease

BACKGROUND Among patients with stable coronary disease and moderate or severe ischemia, whether clinical outcomes are better in those who receive an invasive intervention plus medical therapy than in those who receive medical therapy alone is uncertain. METHODS We randomly assigned 5179 patients with moderate or severe ischemia to an initial invasive strategy (angiography and revascularization when feasible) and medical therapy or to an initial conservative strategy of medical therapy alone and angiography if medical therapy failed. The primary outcome was a composite of death from cardiovascular causes, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. A key secondary outcome was death from cardiovascular causes or myocardial infarction. RESULTS Over a median of 3.2 years, 318 primary outcome events occurred in the invasive-strategy group and 352 occurred in the conservative-strategy group. At 6 months, the cumulative event rate was 5.3% in the invasive-strategy group and 3.4% in the conservative-strategy group (difference, 1.9 percentage points; 95% confidence interval [CI], 0.8 to 3.0); at 5 years, the cumulative event rate was 16.4% and 18.2%, respectively (difference, 121.8 percentage points; 95% CI, 124.7 to 1.0). Results were similar with respect to the key secondary outcome. The incidence of the primary outcome was sensitive to the definition of myocardial infarction; a secondary analysis yielded more procedural myocardial infarctions of uncertain clinical importance. There were 145 deaths in the invasive-strategy group and 144 deaths in the conservative-strategy group (hazard ratio, 1.05; 95% CI, 0.83 to 1.32). CONCLUSIONS Among patients with stable coronary disease and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of ischemic cardiovascular events or death from any cause over a median of 3.2 years. The trial findings were sensitive to the definition of myocardial infarction that was used